Use char overload for single-character string methods

Proprietary

Convert string methods with single-character string literals to use char overloads for better performance.

OpenRewrite.Recipes.CSharp.CodeQuality.Performance.FindOptimizeStartsWith

mod run . --recipe=OpenRewrite.Recipes.CSharp.CodeQuality.Performance.FindOptimizeStartsWith

Install it once, then run it on every repository under the current directory. New to the Moderne CLI? Set it up.